If $A$ is any set, then
$A \cup A' = \phi $
$A \cup A' = U$
$A \cap A' = U$
None of these
If $U=\{a, b, c, d, e, f, g, h\},$ find the complements of the following sets:
$B=\{d, e, f, g\}$
Taking the set of natural numbers as the universal set, write down the complements of the following sets:
$\{ x:x$ is an even natural number $\} $
Let $n(U) = 700,\,n(A) = 200,\,n(B) = 300$ and $n(A \cap B) = 100,$ then $n({A^c} \cap {B^c}) = $
Given $n(U) = 20$, $n(A) = 12$, $n(B) = 9$, $n(A \cap B) = 4$, where $U$ is the universal set, $A$ and $B$ are subsets of $U$, then $n({(A \cup B)^C}) = $
If $A$ and $B$ are two given sets, then $A \cap {(A \cap B)^c}$ is equal to